Weather and Traffic

Tropical wave expected to soak South Florida, new area being watched

Update 8 p.m.: Shower activity associated with a tropical wave in the Caribbean has increased over the last few hours, but the system remains disorganized and the chances of tropical development over the next 48 hours has dropped to 20 percent, according to the National Hurricane Center.

Upper level winds will conspire to keep the system — named 99-L — from developing further during the next day or so as it travels west-northwestward at 10 mph.

The hurricane center warns that heavy rains, with potential for flash floods and mudslides, are possible for Hispaniola tonight and tomorrow.

The chances for tropical development over the next five days has also dropped slightly to 50 percent.

Update 2 p.m.: Thunderstorm activity has increased with the tropical wave being tracked between Cuba and the central Bahamas, but upper-level winds continue to tear at the system, limiting potential for now.

As of the 2 p.m. update, the National Hurricane Center is giving the system a 30 percent chance of tropical development over the next two days and a 60 percent chance over five days.

The system, dubbed 99-L, is expected to enter the Gulf of Mexico early next week where conditions better for it to better organize.

Gusty winds and heavy rain are expected to spread into South Florida and the Florida Keys this weekend, with Palm Beach County feeling the impacts early Sunday morning through Tuesday.

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The tropical wave that South Florida has been anxiously watching all week is down to a 60 percent chance of development through Tuesday and has shifted its path more to the south.

As of the 8 a.m. advisory, so-called 99-L was stretched across eastern Cuba and into the central Bahamas, with just a tiny piece of extreme southeast Florida in the development area.

The Air Force Reserve Hurricane Hunter that was scheduled to investigate the area of low pressure this morning was canceled as the chances of development over the next 48 hours plummeted to 20 percent.

Palm Beach County was not in the thatched development area on the center’s map.

Forecasters said the environment could prove more friendly for 99-L as it moves slowly toward the west-northwest through the Florida Straits and into the Gulf of Mexico.

“Interests in Florida and the Florida Keys should continue to monitor the progress of this disturbance since some impacts, such as heavy rains and gusty winds, could begin over the weekend and continue through early next week,” forecasters wrote in the 2 a.m. discussion.

The system, which some meteorologists thought had the potential to hit South Florida as a Category 1 storm, may be joined in the Gulf by another area of interest that was given a low chance _ just 10 percent _ chance of growing into something more over the next five days.

A small area of disturbed weather west of Texas’ Gulf coast is expected to reach land over the weekend, but is not expected to experience much development before that time.

Despite the shift south of 99-L, forecasters at the National Weather Service in Miami are still expecting a breezy wet weekend because of the tropical wave’s very large size.

Heavy rainfall will be the “primary threat.” Depending on the continued progress of the wave, several inches of rain could fall in parts of South Florida through early next week.

FPL spokesman Bud Fraga said Friday that FPL has told workers from utilities in other states it had asked to come to Florida to assist it to stay put.

“While the forecast continues to remain uncertain, the trend over the past 24 hours is for a decreasing threat to South Florida with this system, and a more southern track for any possible development,” forecasters wrote. “However, this does not mean that South Florida is in the clear.”

Monday and Tuesday are likely to be the wettest days as the the counter clockwise churn of 99-L pulls up tropical moisture as it moves through the Florida Straits.

Meteorologists have wrestled with forecasts for Invest 99-L all week as computer models spit out a wide range of disparate paths and intensities.

The National Hurricane Center has never had it at more than an 80 percent chance of development, but there were signals even it was frustrated with the differing models. One forecaster tweeted that trying to predict 99-L’s future was making his hair grey and that the system was testing the limits of science.

“It’s not completely shocking it hasn’t developed yet because that’s what the models have been saying, but they are now pretty certain it won’t be a hurricane,” said Bob Henson, a meteorologist and blogger for Weather Underground. “But it’s really too soon to let our guard down.”

The question now will be whether the system makes it into the Gulf of Mexico with enough rotation to become a tropical system, and if so, how strong it will get and where it will go, Henson said.